Slidable spring-biased grip for a handheld writing implement

ABSTRACT

A slidable spring-biased grip assembly connectible to a handheld writing implement for reducing pressing force applied to an external surface during writing for protection thereof. The grip assembly includes an elongated assembly body, a tip connected to an end thereof, a gripping member configured to be axially slidable thereon, and a tension member resiliently and mechanically communicating between the tip and the gripping member, configured to resiliently bias, and slidably urge, the gripping member in a direction away from the tip. The assembly may further comprise a cushioned grip removably sleeved over gripping member and advertising material may be imprinted on an outer surface of the handheld implement.

FIELD OF THE INVENTION

The present invention relates to field of a slidable spring-biased grip assembly connectible to a handheld writing implement, wherein the spring-biased grip is configured to reduce the pressing force applied to an external surface by the writing implement by absorbing part of the force via a tension member.

CROSS-REFERENCE TO RELATED APPLICATION

(Not Applicable)

STATEMENT RE: FEDERALLY SPONSORED RESEARCH/DEVELOPMENT (Not Applicable) BACKGROUND OF THE INVENTION

When people use a handheld writing implement, they often and unavoidably use excessive force while they are pressing it down on an external surface, unable to keep an adequate magnitude of the pressing force. Therefore, it is a well-known problem for a handheld writing implement that the direct touch of its tip under such excessive force causes, frequently and undesirably, flaws or damages on the external surface it is pressed on. Such damages might occur not only on a piece of paper during conventional writing, but also on a touch panel screen if the handheld writing implement is a currently popular PDA stylus, or input pen. Further, such excessive pressure invokes reaction force of a same magnitude, directed from the surface to the handheld implement, that is again transferred to a user's hand or wrist to cause strain and fatigue thereon. It is well known that excessive strain upon the wrist can cause disorders such as Carpal Tunnel Syndrome and arthritis.

Although there are prior patents that attempt to resolve such a problem, each of those patents suffers from deficiencies. For example, U.S. Pat. No. 6,710,267 uses a spring to absorb excessive pressing force for protecting a touch panel by spring-loading the tip only for reducing deformation thereof which does not appear to provide strain relief upon the user.

Other prior art discloses use of a spring in a typical ball point pen for different purposes that all appear to provide for adjustments to pressure upon the pen refill, but not directly upon the user's fingers and suffer from the disadvantage retracting the pen tip itself which may cause shaky writing. U.S. Pat. No. 6,257,787 discloses a ball point pen where a coiled spring is interposed between the cap and a plunger connected to an ink cartridge for adjusting the firmness of writing, but nothing appears to provide strain relief for the grip. U.S. Pat. No. 6,428,232 discloses a ball point pen where a spring, while enclosed in a cap, is interposed between a control member and an ink cartridge for adjusting biasing force. U.S. Pat. No. 6,695,512 appears to disclose use of a spring in a writing instrument interposed between the pen body and a slidable sleeve surrounding the pen tip so as to bias the sleeve over the pen tip to protect the same. Such a design does not appear to provide strain relief during use.

None of the cited prior art however, discloses use of a spring biased grip slidably attached on a portion of a pen that is gripped by a user's fingers. It is desirable, therefore, to provide an invention that cannot only achieve the previously stated purpose of reducing excessive pressing force applied to an external surface for the protection thereof, but also provide a resilient finger-gripping experience during writing and even an aesthetic appeal to the appearance of a handheld writing experience.

SUMMARY OF THE INVENTION

The present invention provides a handheld writing implement that has a slidable spring-biased grip attached on a gripping portion of the handheld writing implement, wherein the spring-biased grip is configured to reduce the pressing force applied to an external surface by the writing implement, by absorbing part of it to a spring. Advantageously, the configuration of the unique slidable spring-biased grip assembly provides for direct support and strain relief upon the user's fingers so that the implement remains substantially stationary while the grip portion slides along the body of the implement. Such a design is an improvement over the prior art designs in that the implement tip may write more smoothly without retracting into the implement body since it is the grip that moves, not the tip. This design also provides for instant user-feedback where the spring is visible, and is more visually pleasing.

The spring-biased grip assembly made in accordance with the present invention includes an elongated assembly body, a tip connected to an end thereof, a gripping member to be gripped by user's fingers, which has a shape of, preferably, a tubular shell wrapped around the assembly body to be slidable axially thereon, and a tension member, preferably a coiled spring, disposed between the tip and gripping member to resiliently bias, and slidably urge, the gripping member away from the tip while preferably maintaining the assembly body stationary. The gripping member may further include a cushioned grip removably sleeved over it. The spring-grip assembly body can be detachably or integrally connected to a body of a typical handheld writing implement, and may have a cylindrical compartment axially defined therein and extended through the tip for accommodating therein a typical ink cartridge.

One of the advantages of the present invention is to provide, through the spring-biased slidable grip described above, an easy and effective means for reducing the occasional but unavoidable excessive pressing force applied by a user to an external surface the writing implement is pressed on, and thereby, an effective protection of the external surface. Another advantage is to provide for a user of the handheld writing implement a resilient and comfortable feeling in writing while holding the spring biased slidable grip. Still another advantage of the present invention is to provide a visually fresh and appealing appearance through the slidable spring-biased grip. In that respect, the handheld writing implement having such a grip would be used as an effective means for advertisement where advertising materials are imprinted on an external surface of the implement body.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a handheld writing instrument with a spring-grip assembly in the first preferred embodiment of the present invention;

FIG. 2 is a side elevational view of a handheld writing instrument with a spring-grip in the first preferred embodiment of the present invention;

FIG. 3 is a top plan view of a handheld writing instrument with a spring-grip assembly in the first preferred embodiment of the present invention;

FIG. 4 is an exploded view of a spring-grip assembly in the first preferred embodiment of the present invention;

FIG. 5 is a side elevational view of a spring-grip assembly in the first preferred embodiment of the present invention;

FIG. 6 is a side cross-sectional view of a spring-grip assembly in the first preferred embodiment of the present invention;

FIG. 7 is an exploded view of a spring-grip assembly in the second preferred embodiment of the present invention;

FIG. 8 is a side elevational view of a spring-grip assembly in the second preferred embodiment of the present invention;

FIG. 9 is a side cross-sectional view of a spring-grip assembly in the second preferred embodiment of the present invention; and

FIG. 10 is a perspective view of a handheld writing instrument in the first preferred embodiment, being used in the manner contemplated by the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention generally relates to a handheld writing implement having a slidable grip biased by a spring, which is configured to reduce the pressing force, by absorbing part of it, applied to an external surface by the writing implement.

The first and second preferred embodiments of the present invention will now be described with reference to figures (FIGS.) 1-12, wherein like components are designated by like reference numerals throughout the various figures. Although the invention is generally described in the context of the preferred embodiment, it should be understood that it is shown and described, only by way of illustration of the best mode contemplated of carrying out the invention, but not intended to limit in any way the spirit and scope of the invention to this particular embodiment.

With regard to means for fastening, mounting, attaching or connecting the components of the present invention to form the apparatus as a whole, unless specifically described otherwise, such means are intended to at least encompass conventional fasteners such as machine screws, machine threads, snap rings, hose clamps such as screw clamps and the like, rivets, nuts and bolts, toggles, pins and the like. Components may also be connected by friction fitting, snap fitting, adhesives, or by welding or deformation, if appropriate. Unless specifically otherwise disclosed or taught, materials for making components of the present invention are selected from appropriate materials such as metal, metallic alloys, natural or synthetic fibers, plastics and the like, and appropriate manufacturing or production methods including casting, extruding, injection molding and machining may be used.

FIGS. 1-3 show, respectively, a perspective view, a side elevational view, and a top plan view of a handheld writing implement made according to the present invention. The handheld writing instrument in the preferred embodiment is a typical ball point pen 1. However, such handheld instruments may also include, but are not limited to, for example, a PDA stylus or an input pen. Now referring specifically to FIGS. 1-3, the pen 1 comprises largely an elongated, substantially cylindrical barrel 20, and serially connected thereto, a spring-grip assembly 10 made in the first preferred embodiment of the present invention. The spring-grip assembly 10 forms in itself a lower part of the pen 1 near the pen tip 14. The pen 1 may further comprise a pen cap 21 at an end of the barrel 20 and a typical clip 22 connected thereto.

The present invention contemplates two preferred embodiments for the spring-grip assembly 10. FIGS. 4-6 show, respectively, an exploded view, a side-elevational view, and a side cross-sectional view of the spring-grip assembly 10 in the first preferred embodiment, and FIGS. 7-9 in the second preferred embodiment. As shown in FIGS. 4 and 7, the spring-grip assembly 10 comprises a generally elongated assembly body 11 having a first assembly body end 11 a and a second assembly body end 11 b, a tip 14 connected to the first assembly body end 11 a, a gripping member 14, a cushioned and textured grip 16, and a tension member 17.

The elongated assembly body 11 comprises a tip-connection section 13 a formed adjacent the first assembly body end 11 a to which the tip 14 is connected, a barrel-connection section 13 b formed adjacent the first assembly body end 11 b to which the barrel 20 of a pen 1 is connected, and a grip-sliding section 12 on which a slidable spring biased gripping member 15 and a tension member 17 are engaged. In the first and second preferred embodiments, those connections are achieved via threads respectively formed on two sections 13 a, 13 b as shown in FIGS. 4 and 7, and matching threads formed in inner surfaces of the tip 14 and the barrel 20 of the pen 1. However, any other detachable connection method, such as friction fitting or snap fitting, is also contemplated by the present invention. Further, in one embodiment, the assembly body 11 may be integrally formed with the barrel 20 of the pen 1, or the tip 14.

In both preferred embodiments, the elongated barrel 20 and the three sections of the elongated assembly body 11 have an overall cylindrical configuration with circular cross sections, but in other embodiments, their cross sections may have other geometric shapes, such as a square, rectangle, ellipse, or even a triangle. Further, the grip-sliding section 12 has a smaller circumferential diameter than the barrel connection section 13 b, thereby forming a stopper 12 a in a shape of a circular rim at the junction of the two sections 12 and 13 b for stopping the gripping member 15 from further sliding. The difference in diameter between the two sections 12 and 13 b is set such that when the gripping member 15 and the textured grip 16 are fitted over the grip-sliding section 12, the surface of the grip 16 may be substantially evenly aligned with the surface of the barrel 20. The barrel-connection section 13 b has, again, a slightly smaller diameter than the barrel 20 so that the grip assembly body 11 may be threadably fitted in the barrel 20. Preferably, the tip 14, threadably connected to the tip-connection section 13 a, has a generally tapered cylindrical, or conical shape, but may have any other shapes as well in other embodiments.

Further, if the writing implement is a ball point pen 1 as depicted in FIGS. 1-10, the serially connected barrel 20, the assembly body 10, and the tip 14 may have an elongated compartment 18 axially defined therethrough for removably retaining therein a typical ink cartridge. In that case, the tip 14 may further define an opening connected to the compartment 18 at an end thereof, from which a ball pen tip of the ink cartridge may retractably protrude. The internal mechanisms of a typical ball point pen related with the ink cartridge and the retractable pen tip is well known in the art and will not be described further herein.

In both preferred embodiments, the gripping member 15 is a thin, generally tubular shell having an inner cylindrical orifice of a slightly bigger diameter than the sliding section 12 so as to slidingly sleeve over it. Preferably, it has a length of approximately the first knuckle of an adult finger so as to be comfortably gripped thereby.

While the gripping member 15 is slidable on the grip-sliding section 12, it is biased by a tension member, preferably, a typical coiled spring 17, which is wound around the grip-sliding section 12 to mechanically, and resiliently communicate between the gripping member 15 and the tip 14. The coiled spring 17 is configured such that in the absence of external force acting on the gripping member 15, the coiled spring 17 is slightly compressed, exerting spring force on the gripping member 15 to slidingly urge it toward the second assembly body end 11 b so that it remains engaged with the stopper 12 b. When external force is applied on the gripping member 15 toward the first assembly body end 11 a, the spring 17 is compressed as the gripping member 15 slides down on the grip-sliding section 12, and thereby reducing the pressure transferred to the tip 14 and providing strain relief to the user's fingers.

In the first preferred embodiment shown in FIGS. 4-6, the gripping member 15 is shaped as a straight tubular shell having two identically sized circular flanges 15 a formed at its two opposing ends. In this embodiment, the coiled spring 17 is exposed to view, where one of its ends is directly pressed against one of the circular flanges 15 a while the other end against the tip 14. The other flange of the gripping member 15 is pressed against the stopper 12 b as the gripping member 15 is slidingly urged toward it by the spring 17 in the absence of counteracting external force.

In the second preferred embodiment shown in FIGS. 7-9, the gripping member 15 slidingly engaged upon the grip-sliding section 12 is shaped as a tubular shell, but slightly tapered toward the first assembly body end 11 a. Similarly, it has two circular flanges 15 a formed at its two opposing ends, but of different diameters. As in the first preferred embodiment, one of the flanges 15 a of the gripping member 15, the one with a bigger diameter, is engaged with the stopper 12 b in the absence of external force directed to the first assembly body end 11 a. But the other flange of a smaller diameter is configured to slide over a portion of the tip 14 as the gripping member 15 slides toward the first assembly end 11 a under the external force. In the second preferred embodiment, the coiled spring 17 is still wound around the assembly body 11, but hidden from view, being completely covered by the tapered gripping member 15. Like the first preferred embodiment, one end of the coiled spring 17 is pressed against the tip 14. But in the second preferred embodiment, the other end is pressed, not against one of the two circular flanges 15 a, but against a ring-like flange 15 c formed on the inner surface of the gripping member 15, thereby establishing the necessary mechanical communication between the tip 14 and the gripping member 15.

In both preferred embodiments, the grip-sliding section 12 may further have a guide detent 12 b formed on outer surfaces thereof and the gripping member 15 may define a matching guide recess 15 b thereon, where the detent 12 b and the recess 15 b are formed in the axial direction such that the cylindrical gripping member 15 is prevented from rotating, while permitted to axially slide, on the grip-sliding section 12. Moreover, in both preferred embodiments, a grip 16 made of a cushioned, textured material may be engaged over the gripping member 15 to provide for a user's fingers a comfortable and interesting gripping feeling. Such materials are well known in the art, including but not limited to, foam, leather, elastomeric materials such as rubber, synthetic rubbers such as polyurethane, silicone, or plastics. The grip 16 is preferably detachably and frictionally fitted over it, but may be fixedly incorporated on it by means of adhesives or other permanent attachment means known in the art.

In both preferred embodiments, the barrel 20 of the pen 1, the grip assembly body 11, the tip 14, and the gripping member 15 are manufactured from plastic. But any other suitable rigid materials recognized by one skilled in the art, such as metal, wood, or ceramic materials, may be used.

FIGS. 10 and 11 show how the pen having the spring-biased slidable grip made in the first preferred embodiment according to the present invention is used. FIG. 10 shows a user holding the pen without applying pressing force so that the pen refill 100 is not contacting any surface, while merely gripping with fingers the gripping member 15 and the textured grip 16 retained thereon. As the user presses down on the pen for writing as shown in FIG. 11, the downward pressure is applied to the gripping member 15 while the pen refill 100 is contacting a surface. Then the gripping member 15 slides down on the grip-sliding section 12 while compressing the coiled spring 17, and thereby reducing the downward pressure that would otherwise be fully transferred to, and likely to damage, a soft external surface or a piece of paper. FIG. 12 shows how the pen 1 having the spring-biased slidable grip made according to the present invention in the second preferred embodiment is used. As seen in FIG. 12, the gripping member 15 in the second embodiment extends low and conceals the spring 17 and partly covers the tip 14, and thus, better suits a user who has a habit of gripping a pen closer to the tip thereof. The pen refill 100 is contacting a surface.

Since the visually fresh and appealing appearance, particularly, the sliding movement of the gripping member would easily attract the attention of not only a user-buyer, but also other viewers, the handheld writing implement having such a spring biased slidable grip can be an effective vehicle for advertising. Therefore, the present invention also contemplates such a method for advertising as well, wherein advertising materials 30 may be imprinted on any external surface of the writing implement, for instance, on the barrel 20 of the pen 1 as shown in FIGS. 1-3, on the pen cap 21, or even on the clip 22. The advertising material may include, but not be limited to, marks, letters, symbols, pictures, or indicia. It can also be a photo, design, or other pictorial representation. Furthermore, such indicia may be raised or textured to provide even more tactile sensory input to a user. If the advertising material is imprinted on the cap 21 or the clip 22, it may be covered by a transparent cover for protection thereof.

The present invention is capable of other and different embodiments, and its several details are capable of modifications in various respects apparent to those of ordinary skill in the art, all without departing from the essential spirit or attributes of the invention. Therefore, it is desired that the embodiments described hereinbefore be considered in all respects only as illustrative, but not as restrictive. 

1. A handheld writing implement comprising: an elongated barrel having opposing first and second barrel ends; an elongated grip assembly body having opposing first and second assembly body ends, the second assembly body end being connected to the first barrel end; a tip connected to the first assembly body end; a gripping member slidably engaged upon said grip assembly body for gripping by a user's fingers, said gripping member being configured to be slidably movable along a grip-sliding section of said grip assembly body between the assembly body ends; and a tension member disposed in mechanical communication with said tip and said gripping member and configured to counteract external force applied on said gripping member in a direction toward the first assembly body end and slidably urge said gripping member toward the second assembly body end for providing strain relief to the user's fingers.
 2. The handheld writing implement as in claim 1, wherein said grip-sliding section is substantially cylindrical in shape.
 3. The handheld writing implement as in claim 2, wherein said gripping member is an elongated generally tubular shell slidably engaged to said grip-sliding section.
 4. The handheld writing implement as in claim 3, wherein said grip assembly body further comprises a substantially cylindrical barrel-connection section adjacent the second assembly body end for connection to said barrel, said barrel-connection section having a larger diameter than said grip-sliding section to form a stopper at a junction therebetween for retaining said tubular shell upon said grip-sliding section.
 5. The handheld writing implement as in claim 4, wherein said tubular shell has first and second outwardly extending flanges formed at two opposing ends thereof adjacent to the first and second assembly body ends respectively, said second flange being configured to engage the stopper when said tubular shell is slidingly urged in a direction toward the second assembly body end by said tension member.
 6. The handheld writing implement as in claim 3, wherein said grip-sliding section has a guide detent formed on an outer surface thereof and said tubular shell has a guide recess formed on a portion thereof, said guide detent and recess being configured to mateably engage each other and prevent rotation of said tubular shell about a longitudinal axis of said grip assembly body.
 7. The handheld writing implement as in claim 3, further comprising a cushioned grip removably engaged to said tubular shell.
 8. The handheld writing implement as in claim 5, wherein said tension member is a coiled spring wrapped around said grip assembly body.
 9. The handheld writing implement as in claim 8, wherein said coiled spring is interposed between said tip and said gripping member.
 10. The handheld writing implement as in claim 9, wherein said coiled spring is interposed between said first flange of said tubular shell and said tip.
 11. The handheld writing implement as in claim 8, wherein said generally tubular shell is tapered toward said first flange.
 12. The handheld writing implement as in claim 11, wherein said tubular shell further comprises a ring-like flange formed on an inner surface thereof, and said coiled spring is interposed between said ring-like flange of said tubular shell and said tip.
 13. The handheld writing implement as in claim 12, wherein said tubular shell conceals said coiled spring thereunder.
 14. The handheld writing implement as in claim 1, wherein said tip is generally cylindrically tapered in shape.
 15. The handheld writing implement as in claim 14, wherein said tip is threadably connected to the first assembly body end.
 16. The handheld writing implement as in claim 1, wherein the second assembly body end is threadably connected to the first barrel end.
 17. The handheld writing implement as in claim 1, wherein said barrel and said grip assembly body are integrally formed.
 18. The handheld writing implement as in claim 1, wherein said grip assembly body and said gripping member are fabricated of plastic material.
 19. The handheld writing implement as in claim 1, wherein advertising material is imprinted on an outer surface of said writing implement for advertisement.
 20. A spring-grip assembly for connection to a handheld writing implement comprising: an elongated assembly body having opposing first and second assembly body ends; a tip connected to the first assembly body end; a gripping member slidably engaged upon said grip assembly body for gripping by a user's fingers, said gripping member being configured to be slidably movable along a grip-sliding section of said grip assembly body between the assembly body ends; and a tension member disposed in mechanical communication with said tip and said gripping member and configured to counteract external force applied on said gripping member in a direction toward the first assembly body end and slidably urge said gripping member toward the second assembly body end for providing strain relief to the user's fingers.
 21. The spring-grip assembly body as in claim 20, wherein said grip-sliding section is substantially cylindrical in shape.
 22. The spring-grip assembly body as in claim 21, wherein said gripping member is an elongated generally tubular shell slidably engaged to said grip-sliding section.
 23. The spring-grip assembly body as in claim 22, wherein said grip assembly body further comprises a substantially cylindrical implement-connection section adjacent the second assembly body end for connection to the writing implement, said implement-connection section having a larger diameter than said grip-sliding section to form a stopper at a junction therebetween for retaining said tubular shell upon said grip-sliding section.
 24. The spring-grip assembly body as in claim 23, wherein said tubular shell has first and second outwardly extending flanges formed at two opposing ends thereof adjacent to the first and second assembly body ends respectively, said second flange being configured to engage the stopper when said tubular shell is slidingly urged in a direction toward the second assembly body end by said tension member.
 25. The spring-grip assembly body as in claim 22, wherein said grip-sliding section has a guide detent formed on an outer surface thereof and said tubular shell has a guide recess formed on a portion thereof, said guide detent and recess being configured to mateably engage each other and prevent rotation of said tubular shell about a longitudinal axis of said grip assembly body.
 26. The spring-grip assembly body as in claim 22, further comprising a cushioned grip removably engaged to said tubular shell.
 27. The spring-grip assembly body as in claim 24, wherein said tension member is a coiled spring wrapped around said assembly body.
 28. The spring-grip assembly body as in claim 27, wherein said coiled spring is interposed between said tip and said gripping member.
 29. The spring-grip assembly body as in claim 28, wherein said coiled spring is interposed between said first flange of said tubular shell and said tip.
 30. The spring-grip assembly body as in claim 27, wherein said generally tubular shell is tapered toward the first flange.
 31. The spring-grip assembly body as in claim 30, wherein said tubular shell further comprises a ring-like flange formed on an inner surface thereof, and said coiled spring is interposed between said ring-like flange of said tubular shell and said tip.
 32. The spring-grip assembly body as in claim 29, wherein said tubular shell conceals said coiled spring thereunder.
 33. The spring-grip assembly body as in claim 20, wherein said tip is generally cylindrically tapered in shape.
 34. The spring-grip assembly body as in claim 33, wherein said tip is threadably connected to the first assembly body end.
 35. The spring-grip assembly body as in claim 20, wherein said grip assembly body and said gripping member are fabricated of plastic material.
 36. The spring-grip assembly body as in claim 23, wherein said implement-connection section comprises threads formed thereon for threadable engagement to the writing implement.
 37. A method of advertising comprising the steps of: a) providing a handheld writing implement comprising: 1) an elongated barrel having opposing first and second barrel ends, 2) an elongated grip assembly body having opposing first and second assembly body ends, the second assembly body end being serially connected to the first barrel end, 3) a tip connected to the first assembly body end, 4) a gripping member slidably engaged upon the grip assembly body for gripping by a user's fingers, the gripping member being configured to be slidably movable along a grip-sliding section of said grip assembly body between the assembly body ends, and 5) a tension member disposed in mechanical communication with the tip and the gripping member and configured to counteract external force applied on the gripping member in a direction toward the first assembly body end and slidably urge the gripping member toward the second assembly body end for providing strain relief to the user's fingers; and b) imprinting advertising material on an outer surface of the handheld writing implement.
 38. The method of advertising as in claim 37, wherein the step of providing a handheld writing implement further comprises removably connecting a retractable cap to the second barrel end.
 39. The method of advertising as in claim 38, wherein the step of imprinting advertising material comprises imprinting advertising material on an outer surface of the retractable cap. 